Re: [linux-dvb] [PATCH] Userspace tuner

Manu Abraham
2007-09-14T12:00:53Z

Joerg Roedel wrote:
> On Fri, Sep 14, 2007 at 11:57:59AM +0400, Manu Abraham wrote:
>>>>> What do you think about IOMMU?
>>>>>
>>>>>
>>>> Just because AMD or INTEL want to invent some whizzy new technology it
>>>> doesn't say anything about the TV card development and retail business.
>>>> Intel and AMD have teams of Linux engineers helping operating system
>>>> developers bring their ideas and technologies to new platforms. That's a
>>>> million miles away from any of the TV board vendors I know of, who have
>>>> little or NO fulltime linux developers and consider the < 5% market
>>>> fringe at best.
>>>>
>>> it helps to virtualize devices and introduces newer features for that.
>>> Some interesting projects could be derrived out of that, there are
>>> quite a few interesting papers floating around how drivers could be
>>> handled in future.
>>>
>> IOMMU can be considered similar to the AGP GART, which is similar,
>> remapping the Addresses, as far as i understand.
>
> Common new IOMMUs have only very few in common with the AGP GART. In
> fact, with current modern IOMMU hardware it will be possible to
> implement secure userspace device drivers that are even able to do DMA.
> This is not possible with the GART.
>
>> Though you get a physical to virtual translation, what about interrupts,
>
> Modern IOMMUs are able to remap interrupts. This will solve the problem
> with PCI interrupt sharing.

What CPU's are we talking about ?

Thanks for the explanation.

Manu